For "pester":
* Harass: This implies a more aggressive and persistent form of bothering.
* Badger: Similar to harass, but often used for repeated, insistent requests.
* Nag: Used for constant, annoying reminders or requests.
* Annoy: A more general term for causing someone to be slightly irritated.
* Bother: A general term for causing someone to be troubled or upset.
* Torment: A stronger word that implies prolonged, intense annoyance or suffering.
* Harrow: To cause someone intense worry or distress.
For "irritate":
* Annoy: A more general term for causing someone to be slightly irritated.
* Vex: To cause someone to be slightly angry or frustrated.
* Provoke: To deliberately make someone angry or upset.
* Aggravate: To make an existing problem worse.
* Infuriate: To make someone extremely angry.
* Enrage: Similar to infuriate, but often used to describe a feeling of intense, uncontrolled anger.
* Exasperate: To cause someone to become extremely frustrated or annoyed.
The best word to use will depend on the specific context and the level of intensity you want to convey.